Clutch



Dec.y 20,- 1938. H, J'. DUNKEIQOW 2,140,619

Dec. `20, 1938. H. J. DUNKELOW CLUTCH Filed Feb. 4, 1937 2 Sheets-Sheet2 Paten-fed Dec. zo, 193s CLUTCH Henry J. Dnnkelow, Racine, Wis.,assigner to Twin Disc Clutch Company, Racine, Wis., a

corporation of Wisconsin Application February 4, 1937, Serial No.123,947

6 Claims.

My invention relates to clutches and more particularly to that type inwhich-the driving position of the device is established by a mechanicalor positive actuation of the component elements in contrast tospringloading.

One object of my invention is to devise a clutch of the plate type whichis mechanically engaged by operating mechanism that tends to releaseunder the impulse of centrifugal force, thus insuring that the clutchwill run free in the disengaged position. y

A further object is to provide a clutch of the character indicated inwhich engagement is effected through the medium of relatively short,constant throw Vlevers or arms whose releasing movement under theimpulse of centrifugal force isdefinitely limited by contact with aportion of the clutch. l

Additional objects are the securement in a l compact clutch structure ofan adequate mechanical advantage in the operating mechanism for insuringthe application of the required clamping pressure, ease of adjustmentasthe plates wear, and a positive release of the clutch levers or armsduring disengagement.

'I'hese and further objects of myinvention will be set forth in thefollowing specification, reference being had to the accompanyingdrawings, and the novel means by which said objects are eifectuatedwillbe denitely pointed out in they Fig. 3 is a plan view of the clutchconstructionv shown inelig. 1, looking in the direction of the arrow 3in `said figure'.

Fig. 4 is a fragmentary sectional view of the clutch, similanto thatillustrated in Figz 1, Vbut showing the shifting collar occupying aposition in which both clutches are out of engagement.

Fig. 5 is a fragmentary, sectional view of the left hand clutch, asviewed in Fig. 1, showing the relation of one ofthe releasing springsofthe clutch to thefriction plates thereof.

Referring to` Fig. l, the numeral III designates a shaft constitutingone of the rotary parts and which, for purpose of illustration, will bedenoted as the driven member of the clutch construction. A pair ofclutch hubs II is secured to the shaftvby means of keys I2, said hubsbeing placed in abutting relation, as shown clearly in Fig. l, andadjacent the opposite, outer ends of the hubs are mounted the clutchconstructions which are identical in every respect. According- (ci.isz-ss) ly, but one type of construction will be described, referencehereinafter being made to the left hand hub Il, as viewed in Fig. 1.Preferably, the inner or abutting end of each hub II is provided with anenlarged portion I3 for a purpose hereinafter explained.

A plurality of friction, driven disks I4 is secured to the hub Il bymeans of a plurality of keys I5, of which there may be any desirednumber preferably circumferentially disposed in equispaced relationaround the hub. The disks I4 are arranged for axial movement on the keysand endwise movement of the keys toward the right is prevented by thetermination of the associated keyways I6 and toward the left by asplitspring ring I'I which is sutiably mounted i which will be denotedas the driving member ofv the clutch, this part not being shown in thedrawings. 4

The disks I8 are also arranged for axial movement and the two sets ofdisks I4 and I8 are forced into frictional, driving engagement by a pairof clamping members constituted by a backing plate 20 and a pressureplate 2l, the former contacting with the outer face of the group ofdisks and the latter with the inner face, as viewed in Fig. 1, both ofthese plates being secured to the hub I I by the keys I5 so far asmotion of rotation is concerned. The backing plate 20 constitutes afixed abutment against which the indicated friction disks are clampedandv endwise movement of this plate toward the left, as viewed in Fig.1, is restrained by the ring I1. lTheI plates 2li and 2| are actuated toclamp the friction disks by a mechanism hereinafter described and areretracted to a released position by a plurality of springs 22 (see Fig.5), of which there may be any desired number spaced around the hub, andwhich operate within recesses 23 provided in the disks Il, the ends ofthe springs abutting at all times, whether in driving' or releasedposition, against the opposed, inner faces of the plates 20 .and 2 I.

In addition to serving as a clamping member for the two groups of disks,the pressure plate 2-I also functions to maintain the adjusting' memberof the clutchin any predetermined position. To this end, the plate 2| isprovided with a plurality of circumferentially disposed holes 24 whichare preferably equi-spaced around the annulus of the plate. These holesare intended to yas receive the reduced end 25 of-.a lock pin 26 whichis carried and shiftable endwise in a cavity 21 provided in an adjustingring 28 that is threaded v on a floating ring 2i freely shiftable alongthe hub II and drivably connected to the plates and 2| by means of aplurality of driving pins 30, each of which preferably passes throughone of the release springs 22 and sov additionally' serves to guide theaction of these springs. Each pin 36 isfixedly mounted in the oatingring 29, as by a driving t therewith, and is freely slidable through theplates 20 and 2|. 'I'he intermediate portion of the 'pin 26 is enlargedto provide an annular :flange 3|, while the portion of the pin to theright of the ange is reduced as at 32r and slidable in a hole 33 that isaligned with the cavity 21, but is formed with a smaller diameter, thusproviding an internal shoulder 34. A coil spring 35 encircles thereduced portion 32, one end of the spring abutting against the shoulder34 andy the opposite end against the flange 3| to thereby normally forcethe lock pin outwardly of the adjusting ring, or toward the left, asviewed in Fig. 1. A finger grip pin 36 is mounted on the ange 3| and,when the lock pin is occupying the position shown in Fig. 1, extendsoutwardly of the adjusting ring through a slot 31 (see Fig. 3). that isonly slightly wider than the diameter of the finger pin. The left end ofthe slot 31 terminates at the left face of the adjusting ring, while theopposite end of vthe slot communicateswith an arcuate slot 38 that nistransversely disposed with respect thereto and which also communicateswith the cavity 21. In plan view, therefore, the slots 31 and 38together form a T-shaped slot, the arrangement of the slot portions.being such that, when the lock pin is occupying the position shown inFig. A1, the\sides of the slot 31 contact with the finger pin 36 toprevent any rocking movement of the locking pin, but, when the latter isretracted toa position wherein it is free from one of the holes 24 inthe pressure plate 2|, the locking pin may be rotated about its axis toplace the linger pin 36 in one of the arms of the arcuate slot 38,thereby retaining the locking pin in retracted position and permittingan adjustment of the ring 28. In connection with the foregoingdescription, it should be' remembered that the clutch release springs 22always exert pressure against the pressure plate 2|, therefore alwaysmaintaining the latter plate against the co-acting face of the adjustingring 28. The

Llocking pin construction, as disclosed in this` apshown. One end of aclutch arm 4| is pivotally mountedA in each of these slots adjacent theright end of the hub and the opposite end of each arm is bifurcated toprovide a pair of side plates 42 between which is bridged a pintle 43that rotatably supports a roller 44 between the side plates. For apurpose presently explained, the opposite ends of each pintle 43 extendbeyond the side plates 42, as clearly shown in Fig. 3, and each rolleris adapted to bear against an inclined,

Vfor the reception of the trunnions of the customaryshifting fork (notshown). In operation, it is contemplated that the driving disks I8 onthe left handhub will be connected to a suitable driving member, whichwill.be characterized by one condition of operation as regards directionof rotationand speed of rotation, while the disks I8 on the right handhub IIWill be driven by a second member which may be characterizedeither by a motion of rotation opposite to that being applied to thedisks I8 on the left hand hub, or by a motion of rotation in the samedirection, but at a different speed. Accordingly, by this dual type ofclutch construction, the shaft I0 may be subjected to reversals ofrotation as desired, or it may be subjected to changes in rotary speed,dependent upon the character of the driving members which actuate theIrespective driving disks` I8.

Assuming that the cl-utch construction effects reversals inthe motion ofrotation of the shaft I0, it will be obvious from an inspection of Fig.1 that the left hand clutch is in driving engagement with the right handclutch in released position, due to the free action of the springs 22.If it is then desired to eiect a reversal of this condition, theshifting collar 46 is moved toward the right, as viewed in Fig. 1, tothereby engage the rollers A44 on the arms of the right hand clutch anddepress these arms inwardly, or toward the axis of the shaft Ill. Thismovemlent brings each of the indicated rollers'into engagement with theinclined face 45 of the right hand floating ring 29 and thereby shiftsthis ring and the associated adjusting ring 28 and pressure plate 2|toward the right and thus clamps the group of friction disks against thexed abutment constituted by the backing plate 20.

-As the shifting collar 46 moves toward the right, the left hand rollers44 are freed of restraint by the collar 46 and so, under the impulse ofcentrifugal force acting in conjunction with the releasing movement ofthe springs 22 operating through the floating ringl 29, move the clutcharms 4| to the outward position, indicated by the right hand clutch armsin Fig. 1. 'I'his re'- leasing movement of the left hand clutch arms 4|is limited by engagement of the extended ends of each pintle 43 with theadjacent shoulders 5I provided on the clutch portions I3, so that wheneither clutch is in a released position, but with the hub I rotating,those arms which form a part of the released clutch are denitely held ina position at which they may be easily engaged by the shifting collar46. j

As the friction disks I4 and I8 wear, it becomes necessary to readjustthe initial position of the pressure plate 2|, owing to the fixed rangeof movement of the. clutch arms 4'I. This adjustment is effected bymfeans 'of the adjusting rings 28 which are rotatedin the correctdirection to axially move the pressure plate 2| by the insertion of asuitable tool in one of the holes 39, of which there may be provided aplurality extendling inwardly from the periphery of the ring. Prior tosuch an adjustment, of course, the locking pins 26 must be retractedfrom engagement with the pressure plate.

Except during these periods of adjustment, theA pressure plate 2|functions as a base for the release springs 22 and also serves, owing tothe pressure of thesev springs and the engagement'be- .tween the platevand the locking pin, to effectively lock the adjusting ring in anydesired position and this adjustment is maintained regardless of thereversing or'change speed movements of the. clutch mechanism, whichmight otherwise tendto shift the ring from its adjusted position owingto the effect of inertia or momentum of the parts. In other words, therelease springs 22 serve the dual purpose of separating and holding thebacking and pressure plates apart, as well as main- ,1'0 `tainingthrough the pressure plate the'adjusted position of the adjusting ring.l

` 'I'he foregoing clutchconstruction may be used in' the dualarrangement, as illustrated, or singly as desired, and, in either case,provides a very compact construction thatdoes not sacrifice any of themechanical advantages normally required in devices of this type. Therelatively short clutch arms 'eliminate the disadvantages commonlyassociated 'with long, springy arms that 2 are'often used with this typeof construction,

but without weakening the clutch in any particular. One of the mostimportant features .of my improved construction resides in the manner ofdefinitely limiting the releasing movement of the -25 clutch arms, thusproviding a construction which 'plate acting as an abutment againstwhich the 40 friction members are clamped, an adjusting ring forcontacting the clamping plate, a floating ring acting as a carrier forthe adjusting ring, arms swingablev inwardly for engagement with thefloating ring to clamp the members in driving p-l sition, a shiftablecollar for actuating the arms, and separate means for limiting theoutward movement of the arms under the impulse of centrifugal force whenin released position.

2. In a clutch, the combination of frictionv ,members attachable toseparate rotary parts and adapted for driving engagement with eachother, vone of the parts constituting a hub, a backing plate vand aclamping platemounted on the hub, thebacking plate acting as an abutmentagainst which the friction members areclamped, an adjusting ring forcontacting theclamping plate, a floating ring actingv as a carrier forthe adjusting ring, a plurality of arms spaced around the hub, each armbeing pivoted on the hub and having a part for engaging the floatingring to clamp the .members in driving position, and ashiftable collar,for actuating the parts. 3. In a clutch, the combination of frictionmembers attachable to separate rotary parts and- 05 adapted for drivingengagement with each other,

one of theparts constituting a hub having a plurality of shoulders, albacking plate and a clamping plate mounted -on the hub, the backingplate acting as an abutment against which the friction members are"clamped, an adjusting ring for con` tacting the clamping plate, afloating ring acting as a carrier lilor the adjusting ring, a pluralityof arms spaced around the hub, each arm being pivoted on the hub andhaving a part for engaging the floating ring to clamp the members indriving position, a shiftable collar for actuating the arms, and meansprovided on each arm adapted to engage with an adjacent shoulder tolimit the outward movement of the arm under the impulse of centrifugalforce when in released position.

4. In a clutch, the combination of friction members attachable toseparate rotary parts and adapted-for driving engagement with eachother, one of the parts constituting a hub having a plul rality ofshoulders, a backing plate and a clamp-J ing plate mounted on the hub,the backing plate acting as an abutment against which the frictionmembers are clamped, an adjusting ring for contacting the clampingplate, a floating ring acting as a carrier for the adjusting' ring, aplurality of arms spaced ,around the hub, each arm being pivoted on thehub and having a pintle mounted roller for engagement with the floatingring to clampl the members in driving position, and a shiftable collarfor actuating the arms, each pintle being engageable with a shoulder tolimit the releasing movement of the associated arms under the impulse ofcentrifugal force when theclutch is in released position. l

5. -In a clutch, the combination of friction members attachable toseparate rotary parts and adapted for driving engagement with eachother, a backing plate and a clamping plate held against relativerotation fr eiecting the engagement of the members, the backing plateacting as an abutment against which the friction members are clamped;springs interposed between the plates, an adjusting ring for contactingvthe clamping plate, a floating ring acting as a carrier for theadjusting ring, pivoted arms engageable with the floating ring to clampthe members in driving position, and a shiftable collar for actuatingthe arms, the relation of the arms being such that the pressure of thesprings, when the clutch isin driving position, causes a lpressure ofthe arms against the collar in directions substantially normal totheactuating movement thereof.

.6. In dual clutch construction, the combination of a hub having anannular enlargement providing spaced shoulders intermediate the endsthereof, a clutch mountedA at each end of the hub, each clutchcomprising two sets of friction members adapted for driving engagementwith each other, one set being connected to the hub and the other setbeing attachable to a separate rotary part, a backing plate and aclamping plate mounted on the hub, the backing plate acting as anabutment against which the associated friction members are clamped, anadjusting ring contacting the clamping plate, a floating ring acting asa carrier fo`rthe adjusting ring, and two separate groups of arms spacedaround the hub, the arms of each group being pivoted on the hub and eachAengage withanadiacent shoulder to limit the outward movement of thegroups of arms under the impulse of centrifugal forroefwhen the collaris occupying a neutral position.

' may J. nun'mmow.

